iPhone connects and disconnects from Mac

AMAZING! It worked! the Terminal thing:

sudo killall -STOP -c usbd

worked perfectly!

I have an iPhone X and MacBook Air. I have done everything and nothing fixed it. Tried this and seems right. I hope Apple figure it out and fix it in new updates, however, I've seen that people have had this problem from 2013.

Re: Why does my iPad keeps connecting and disconnecting from the new late 2013 iMac

Hey everyone,

I just wanted everyone to have the solution here that way when others experience it, they can hopefully find this solution quickly. Luckily several of you like (MrArifFikri) touched on the solution already, I'll just specify the reason for clarity.

It comes down to power, or more importantly "current". Specifically, with an iPad, USB power consumption is very finicky. So in order for the USB direct connection to your PC, USB hub, or laptop you need to make sure your iPad is charged to over 51%. This will reduce the power draw the iPad will attempt to pull from the USB connection. This should give you flawless charging and syncing capabilities. Now you can sidestep this in some cases by using USB ports on your hub, PC or laptop that are closer to the power supply, or series on the circuit board.

If your iPad is below 51%, you need to use the "cube" or power block that came with your iPad. (The smaller one for your iPhone is not recommended as it lacks the internal transformer that the iPad power block has) The reason for this is that your iPad is attempting to draw too much current from the USB connection through a substrate, i.e. the PC, USB hub or laptop connection. They are only designed to allow a limited amount of current through those connections, thus your iPad continues to "trip" the charging circuit in the device because the power draw is too low.

I hope this helps stop the "doodledee.....deeedledoo" beeping madness you're experiencing! 🙂

If you use multiple desktops with one desktop handling photos (ImageCapture), and another desktop handling iTunes, the madness that ensues is impossible to reconcile, because the macbook pro jumps from one desktop to the other while you are trying to accept a trusted connection, and the iPhone is doing its thing - connecting and disconnecting.

Apart from the very poor/weak management of multiple desktops in OSX (vs Linux), this situation can drive you insane.

The solution is to make sure iTunes is not running when you connect your iPhone - and be on the same desktop as ImageCapture will be when it automatically starts. When you connect your iPhone remove (swipe away) all active apps so that when you get the message to 'trust' this computer you can answer it.

For me this failure to connect occurred when I must have changed from the Wifi to LAN (via thunderbolt) connection. If I changed USB port and set WiFi ON it connected without a problem. But I got curious as to why I could not connect with the first USB port, and the above solution evolved.

This said, I do not agree that Apple should be able to make changes that remove the trust that is already established between devices. It is careless and arrogant behavior to allow customers to be left stranded. The more IT savvy will be able to solve this without resorting to the 'Genius Assistants' in the shops.

Hi Mélody,

I had the same problem and contacted Apple support by phone. Try this:

1. Turn off your MacBook Air

2. Press and hold "Shift+CTRL+ALT(option)+Power" (11 seconds) and release

3. Turn on your MacBook Air as normal

4. Log in

5. Connect your iPhone

This resets your USB ports. In my case, it was a software issue, not a problem with the ports, the cable or the phone itself.

I hope that helps.

Jack

Tried connecting when my phone was on ~16%, didn't work until I switched my phone to low power mode. Then connected with no problems. Tried many of the other fixes on this page, that may have led to it finally working on low power mode...

I am having the same issue. But, I have found that it only occurs when my computer is charging. If I disconnect the charging cord, my iPhone stays connected. Not sure why this works, but for some reason it does.

Connect your iPhone

Run this command in Terminal and it will fix all your problems - sudo killall -STOP -c usbd

Also go to System Preferences > Network > You will see iPhone USB 1, 2 etc. - Select each one and remove them all by pressing the ( - symbol) in the bottom left corner.

Disconnect and reconnect and this should fix all your issues.

It took a bit more than 51%, but this worked for me. I think I charged it up to 70% on my charger before moving it to my iMac, and that ended the eternal connect/disconnect it had been doing previously when I was plugging it into the iMac. I've seen similar behaviour on my car charger so now my suspicion is that the car charger just doesn't have enough juice for a heavily discharged phone. Interesting. Thanks very much for the helpful comment. 🙂

I had issues connecting my new (to me) iphone XS to my macbook pro running High Sierra (becasue I love how solid it runs). None of teh suggestions helped so I manually downloaded and reinstalled iTunes and when I did it told me I needed an extra update to make my iphone work with it. Suddenly everything started working. You can manually download iTines here - https://support.apple.com/kb/dl1977?locale=en_GB

I have a Mid 2015 Macbook pro 15 inch and had so many problems with my iphone continually connecting and disconnecting This "sudo killall -STOP -c usbd" works and I use it every time I use image capture.

Thank you!

This terminal command also worked for me! Much thanks! I've struggled with this for a long long time! And currently I have a failed battery on my Mid 2015 MBPro Retina so only running off of the external power supply and I can still charge my phone now! Thanks again (in this case to: rpmartins) for providing answers to keep us all going!

____________________________

Originally posted by rpmartins:

Try terminal :

sudo killall -STOP -c usbd

____________________________

Peace!

slashGW

I bought an USB Hub with an external power supply, that did the trick for me. No need for an extra cable or change some strange software settings.

Tried many of the solutions offered, but charging my IphoneX more than 60% worked for me. Once it hit that mark, I could get it to connect continuously to my 2015 MacBook Pro.

sudo killall -STOP -c usbd worked for me. Thank you! Such an irritating thing to be happening!

I switched my phone to airplane mode and then it's stopped connecting/disconnecting rapidly.